CN103796570A

CN103796570A - Imaging system

Info

Publication number: CN103796570A
Application number: CN201380002991.0A
Authority: CN
Inventors: 小笠原弘太郎
Original assignee: Olympus Medical Systems Corp
Current assignee: Olympus Corp
Priority date: 2012-04-26
Filing date: 2013-04-24
Publication date: 2014-05-14
Anticipated expiration: 2033-04-24
Also published as: CN103796570B; US8878921B2; WO2013161900A1; US20140104403A1; EP2735261A4; JPWO2013161900A1; EP2735261B1; EP2735261A1; JP5467182B1

Abstract

Provided is an imaging system that is capable of preventing uneven exposure and expanding a dimming range of illumination. An imaging system (1) comprises: a lighting unit (41) that emits illumination light which illuminates a subject; a light receiving unit (244f) where pixels receiving the light and performing photoelectric conversion so as to generate electric signals are arranged in a two-dimensional shape; a reading unit (244g) that sequentially reads the electric signals from the pixels for each horizontal line; and a lighting control unit (42) that emits the illumination light during a period which is a part of the period for reading by the reading unit (244g) of each adjacent line that is a period across two adjacent lines with respect to the lighting unit (41), performs controlling for every two lines of the light receiving unit (244f) so as to equalize the lighting period of each line, and performs controlling so as to equalize the lighting periods of the lines of the light receiving unit (244f) for one frame period.

Description

Camera system

Technical field

The present invention relates to can being arbitrarily designated as from multiple pixels of shooting use read the signal of telecommunication after the pixel output photoelectric conversion of the object camera system as image information.

Background technology

In the past, in medical field, in the time that being observed, the internal organs of the subjects such as patient used endoscopic system.Endoscopic system has: camera head (electron mirror body), and it for example has flexible and is elongated shape, is inserted in the body cavity of subject; Imaging apparatus, it is arranged on the front end of camera head, and in-vivo image is made a video recording; Light supply apparatus, it penetrates the illumination light that subject is thrown light on; Blood processor (ppu), it is made a video recording to imaging apparatus and image processing that the in-vivo image that obtains stipulates; And display device, it can show by blood processor and has carried out image in-vivo image after treatment.Using endoscopic system while obtaining in-vivo image, in the body cavity that insertion section is inserted into subject after, from the front end of this insertion section, to endoceliac biological tissue irradiating illumination light, imaging apparatus is made a video recording to in-vivo image.The in-vivo image that the users such as doctor show according to display device carries out the observation of the internal organs of subject.

The imaging apparatus having as this endoscopic system, applies CMOS(Complementary Metal Oxide Semiconductor: complementary metal oxide semiconductors (CMOS) sometimes) sensor.The Rolling shutter mode image data generating that cmos sensor is exposed or read by the timing of staggering according to every row.

And, in order to prevent because the uneven image quality that causes of exposure of every row of imaging apparatus reduces, be known to following technology: with the exposure of imaging apparatus or readout interval synchronously, by PWM(Pulse Width Modulation: pulsewidth modulation) control with lighting of throwing light on of the cycle of regulation and extinguish (with reference to patent documentation 1).

Prior art document

Patent documentation

Patent documentation 1: TOHKEMY 2007-318581 communique

Summary of the invention

The problem that invention will solve

But, in above-mentioned patent documentation 1, in order to eliminate the exposure inequality of every row of imaging apparatus, need to switch at a high speed lighting and extinguishing of illumination, so, according to the limit of switching the speed of lighting and extinguishing of throwing light on, the variable-width of the irradiation time of illumination light can not be got larger, and existence cannot expand the problem points of the dimming scope of illumination.

The present invention In view of the foregoing completes, and its object is, the camera system that can prevent exposure inequality and expand the dimming scope of illumination is provided.

For solving the means of problem

In order to solve above-mentioned problem and to achieve the goal, camera system of the present invention is characterised in that, this camera system has: Lighting Division, and it penetrates the illumination light that subject is thrown light on; Light accepting part, it is two-dimentional shape and is arranged with the pixel that generates the signal of telecommunication by receiving light and carrying out opto-electronic conversion; Reading unit, it reads the described signal of telecommunication according to each horizontal line successively from described pixel; And lighting control section, it is controlled as follows to described Lighting Division: between the reading duration of the 1st horizontal line of crossing over described reading unit and in during between the reading duration of the 2nd horizontal line, penetrate the described illumination light of the pulse type centered by the finish time between the reading duration of described the 1st horizontal line, wherein, described the 2nd horizontal line is adjacent with described the 1st horizontal line and immediately after the 1st horizontal line, read.

And camera system of the present invention is characterised in that, in foregoing invention, carries out the control of described lighting control section every 2 row.

And, camera system of the present invention is characterised in that, in foregoing invention, described camera system also has lightness test section, this lightness test section detects the lightness of the light being received by described light accepting part, described lighting control section is according to the testing result of described lightness test section, and the PWM that carries out the pulse width that changes the described illumination light of described pulse type centered by the finish time between the reading duration of described the 1st horizontal line controls.

Invention effect

According to camera system of the present invention, lighting control section is controlled as follows to Lighting Division: in during the part between the reading durations adjacent 2 row, that by reading unit, adjacent each row is read of crossing over light accepting part, penetrate illumination light, every 2 of light accepting part advance exercise the illumination in each row during equal control, make all to equate during the illumination of every row of the light accepting part in 1 image duration.Thus, performance can prevent the effect of the dimming scope of exposure inequality and expansion illumination.

Accompanying drawing explanation

Fig. 1 is the figure that the schematic configuration of the endoscopic system of an embodiment of the invention is shown.

Fig. 2 is the block diagram that the functional structure of the major part of the endoscopic system of an embodiment of the invention is shown.

Fig. 3 is the exposure of the imaging apparatus when photography of endoscopic system of an embodiment of the invention is shown or the figure that lights or extinguish the relation of timing that reads timing and light supply apparatus.

The specific embodiment

Below, as for implementing mode of the present invention (hereinafter referred to as " embodiment "), the therapeutic medical endoscopic system of the endoceliac image of the subjects such as patient being made a video recording and show is described as camera system.And the present invention can't help this embodiment and limits.And then, in the record of accompanying drawing, to marking same label with a part.

Fig. 1 is the figure that the schematic configuration of the endoscopic system of an embodiment of the invention is shown.Fig. 2 is the block diagram that the functional structure of the major part of the endoscopic system of an embodiment of the invention is shown.

As depicted in figs. 1 and 2, endoscopic system 1 has: the 2(of endoscope electron mirror body), it,, by leading section being inserted in the body cavity of subject, is made a video recording to the in-vivo image of subject; Blood processor 3(ppu), the in-vivo image that it obtains being made a video recording by endoscope 2 is implemented the image processing of regulation, and controls uniformly the action of endoscopic system 1 entirety; Light supply apparatus 4, it produces the illumination light penetrating from the front end of endoscope 2; And display device 5, its demonstration has been implemented image in-vivo image after treatment by blood processor 3.

Endoscope 2 has: insertion section 21, and it has flexible and is elongated shape; Operating portion 22, it is connected with the base end side of insertion section 21, accepts the input of various operation signals; And general cable 23, it extends to the different direction of the direction of extending from insertion section 21 from operating portion 22, is built-in with the various cables that are connected with blood processor 3 and light supply apparatus 4.

Insertion section 21 has: leading section 24, and it is built-in with imaging apparatus 244, and this imaging apparatus 244 will become two-dimentional shape by receiving light and carrying out the Pixel arrangement that opto-electronic conversion generates signal; Bending bending section 25 freely, it is made up of multiple curved block; And thering is the flexible pipe portion 26 of flexible strip, it is connected with the base end side of bending section 25.

Leading section 24 has: photoconduction 241, and it uses the formation such as glass fibre, becomes the guide path of the light that light supply apparatus 4 sends; Illuminating lens 242, it is arranged on the front end of photoconduction 241; Assemble the optical system 243 of use; And imaging apparatus 244, it is arranged on the image space of optical system 243, receives the light assembled by optical system 243 and is the signal of telecommunication by its opto-electronic conversion, implements the signal processing of regulation.

Optical system 243 is used one or more lens to form, and has and changes the optical zoom function of the angle of visual field and change bifocal focus function.

Imaging apparatus 244 has the 244a of sensor portion that the light from optical system 243 is carried out to opto-electronic conversion output electrical signals, the 244b(of AFE (analog front end) portion that the signal of telecommunication of being exported by the 244a of sensor portion is carried out to noise remove and A/D conversion is hereinafter referred to as " 244b of AFE portion "), to the walk abreast/serial conversion of digital signal (picture signal) by the 244b of AFE portion output and send it to outside P/S converter section 244c, the timing generator 244d of the pulse of the various signal processing in driving timing and the 244b of AFE portion and the P/S converter section 244c of the generation 244a of sensor portion, and the imaging control part 244e that the action of imaging apparatus 244 is controlled.Imaging apparatus 244 is cmos sensors.

The 244a of sensor portion has: light accepting part 244f, and it becomes two-dimensional-matrix-like by having respectively multiple Pixel arrangements of accumulating the amplifier that the photodiode of the electric charge corresponding with light quantity amplifies with the electric charge that photodiode is accumulated; And reading unit 244g, its pixel that is at random set as reading object from multiple pixels of light accepting part 244f, reads the signal of telecommunication as image information successively according to each horizontal line.And, in the sensitive surface of light accepting part 244f, be provided with color filter for each pixel.

The 244b of AFE portion have the noise contribution comprising in the reduction signal of telecommunication (simulation) the 244h of reducing noise portion, adjust the amplification (gain) of the signal of telecommunication and maintain the AGC(Auto Gain Control of constant output level: automatic gain control) 244i of portion and the signal of telecommunication as image information (picture signal) exported via the 244i of the AGC portion A/D converter section 244j that carries out A/D conversion.The 244h of reducing noise portion for example uses correlated-double-sampling (Correlated Double Sampling) method to carry out the reduction of noise.

Imaging control part 244e controls the exercises of leading section 24 according to the setting data receiving from blood processor 3.Imaging control part 244e uses CPU(Central Processing Unit: CPU) and record the formation such as depositor of various programs.

Operating portion 22 has: crooked knob 221, and it makes bending section 25 be bent upwards at above-below direction and right and left; Treatment instrument insertion section 222, it is inserted into the treatment instruments such as live body pliers, laser scalpel and inspection probe in the body cavity of subject; And as multiple switches 223 of operation inputting part, they except the operation index signal of blood processor 3, light supply apparatus 4, also input supply gas unit, send water unit and send the operation index signal of the peripheral equipments such as mist unit.The treatment instrument inserting from treatment instrument insertion section 222 is outstanding from peristome (not shown) via the treatment instrument passage (not shown) of leading section 24.

General cable 23 is at least built-in with the set cable 245 that photoconduction 241 and the one or more holding wires of harness form.General cable 23 has with respect to blood processor 3 and light supply apparatus 4 dismounting adapter portion 27 freely.

Adapter portion 27 has FPGA(Field Programmable Gate Array: field programmable gate array) 271.FPGA271 receives the signal of telecommunication of inputting from imaging apparatus 244, and the signal of telecommunication receiving is outputed to blood processor 3.In addition, FPGA271 also can carry out according to the setting data from blood processor 3 control of each structural portion of imaging apparatus 244.

Then, the structure of blood processor 3 is described.Blood processor 3 has S/P converter section 301, image processing part 302, lightness test section 303, light modulation portion 304, reads address setting portion 305, drives signal generating unit 306, input part 307, recording unit 308, control part 309, reference clock generating unit 310.

S/P converter section 301 carries out serial/parallel conversion to the picture signal of inputting from adapter portion 27 (signal of telecommunication), and is outputed to image processing part 302.

Image processing part 302, according to the picture signal of inputting from S/P converter section 301, generates the in-vivo image being shown by display device 5.Image processing part 302 has the 302a of portion of change simultaneously, the 302b(of blank level adjustment portion hereinafter referred to as " WB adjustment part 302b "), gain adjustment part 302c, γ correction unit 302d, D/A converter section 302e, the 302f of format change portion, memorizer 302g, rest image memorizer 302h for sampling.

The 302a of portion of change simultaneously changes the image information of inputting as Pixel Information simultaneously.The RGB image information after changing is outputed to successively WB adjustment part 302b by the 302a of portion of change simultaneously, and, a part of RGB image information is outputed to sampling and use memorizer 302g, for the image analysis of lightness detection etc.

WB adjustment part 302b adjusts the white balance of RGB image information automatically.Particularly, WB adjustment part 302b, according to the colour temperature comprising in RGB image information, adjusts the white balance of RGB image information automatically.

Gain adjustment part 302c carries out the gain adjustment of RGB image information.The rgb signal having carried out after gain adjustment is outputed to γ correction unit 302d by gain adjustment part 302c, and, a part of rgb signal is outputed to rest image memorizer 302h, show or emphasize that image shows for rest image demonstration, enlarged image.

The gray correction (γ correction) of RGB image information is carried out in γ correction unit 302d and display device 5 accordingly.

The RGB image information after the gray correction by γ correction unit 302d output is converted to analogue signal by D/A converter section 302e.

The file format that the 302f of format change portion uses the dynamic image that is converted to image information after analogue signal and changes to high definition mode etc., and outputed to display device 5.

Lightness test section 303, according to detecting the lightness grade corresponding with each pixel by sampling by the RGB image information that memorizer 302g keeps, is recorded in the lightness grade detecting to be located in inner memorizer, and outputed to control part 309.And lightness test section 303, according to the lightness rating calculation gain adjustment value and the rayed amount that detect, outputs to gain adjustment part 302c by gain adjustment value, on the other hand, rayed amount is outputed to light modulation portion 304.

Light modulation portion 304, under the control of control part 309, according to the rayed amount being calculated by lightness test section 303, sets the light quantity, the luminous timing etc. that are produced by light supply apparatus 4, and the dim signal of the condition that comprises this setting is outputed to light supply apparatus 4.

Reading address setting portion 305 has reading subject pixels and reading the function that order is set in the sensitive surface of the 244a of sensor portion., read address setting portion 305 and there is the function that the address of the pixel that the 244b of AFE portion is read from the 244a of sensor portion is set.And, read address setting portion 305 address information of reading subject pixels setting outputed to the 302a of portion of change simultaneously.

Drive signal generating unit 306 under the control of control part 309, generate the driving timing signal for driving imaging apparatus 244, send to timing generator 244d via the holding wire of the regulation comprising in set cable 245.This timing signal comprises the address information of reading subject pixels.

Input part 307 is accepted the input of the various signals such as the action index signal of the action that is used to indicate endoscopic system 1.

Recording unit 308 is used flash memory, DRAM(Dynamic Random Access Memory: dynamic random access memory) etc. semiconductor memory realize.Recording unit 308 record comprises the data for making various programs and the needed various parameters of action of endoscopic system 1 etc. that endoscopic system 1 moves.And, the identifying information of recording unit 308 record processing units 3.Here intrinsic information (ID), model year, specification information, load mode and transfer rate etc. that, identifying information comprises blood processor 3.

Control part 309 uses the formations such as CPU, comprises imaging apparatus 244 and light supply apparatus 4 in the driving control of interior each structural portion and for input and output control of the information of each structural portion etc.The setting data that control part 309 is controlled use via the holding wire of the regulation comprising in set cable 245 by shooting sends to imaging control part 244e.The phototiming of the each row that comprises imaging apparatus 244 and the synchronizing signal of reading timing are outputed to light supply apparatus 4 by control part 309.

Reference clock generating unit 310 generates the reference clock signal as the action benchmark of each structural portion of endoscopic system 1, and each structural portion of endoscope system 1 is supplied with the reference clock signal generating.

Then, the structure of light supply apparatus 4 is described.Light supply apparatus 4 has Lighting Division 41 and lighting control section 42.

Lighting Division 41 penetrates the illumination light that subject is thrown light on.Lighting Division 41 has light source 41a and light source drive 41b.

Light source 41a uses White LED to form, and under the control of lighting control section 42, produces white light.The light that light source 41a produces irradiates from leading section 24 to subject via collecting lens (not shown) and photoconduction 241.

Light source drive 41b, by light source 41a being supplied with to electric current under the control of lighting control section 42, makes light source 41a produce white light.

Lighting control section 42 is controlled as follows to Lighting Division 41: in during the part between reading duration during adjacent 2 row of crossing over light accepting part 244f, that by reading unit 244g, adjacent each row is read, penetrate illumination light, every 2 of light accepting part 244f advance exercise the illumination in each row during equal control, make all to equate during the illumination of every row of the light accepting part 244f in 1 image duration.Particularly, lighting control section 42 receives the synchronizing signal of inputting from control part 309, and receive the dim signal of inputting from light modulation portion 304, the electric power of light source drive 41b being supplied with to light source 41a according to these signals is controlled, and, the driving timing of light source drive 41b driving light source 41a is carried out to PWM control.

Display device 5 receives the in-vivo image being generated by blood processor 3 and shows from blood processor 3 via image cable.Display device 5 is used liquid crystal or organic EL(Electro Luminescence: electroluminescent) form.

The exposure of the imaging apparatus 244 when having the photography of endoscopic system 1 of above structure or the relation of lighting or extinguishing timing of reading timing and light supply apparatus 4 describe.

Fig. 3 is the exposure of the imaging apparatus 244 when the photography of endoscopic system 1 is shown or the figure that lights or extinguish the relation of timing that reads timing and light supply apparatus 4.In addition, in Fig. 3, transverse axis express time.And, Fig. 3 (a) illustrate imaging apparatus 244 each row exposure or read timing, 1H represents between the reading duration of each row.Fig. 3 (b) illustrates the delustring of light supply apparatus 4 or lights timing.Fig. 3 (c) illustrates the delustring of light supply apparatus 4 or lights another example of timing.

As shown in Figure 3, lighting control section 42 is read the 2 behavior cycles of picture signal from light accepting part 244f with reading unit 244g, and the ignition period of the illumination to light supply apparatus 4 carries out PWM control.For example, lighting control section 42 is read 2 row of picture signal and is controlled as one group (1 unit) using reading unit 244g from light accepting part 244f, make take this 2 row read timing border as benchmark, with the ignition period of the illumination of the equal cyclomorphosis light supply apparatus 4 in front and back, thereby make to equate with behavior unit during illumination.

As shown in Figure 3 (b), lighting control section 42 is controlled as follows to Lighting Division 41: cross over the adjacent n capable (n=natural number) of light accepting part 244f and n+1 during capable, by reading unit 244g to adjacent n during the part between the capable and capable reading duration of reading of n+1 in ejaculation illumination light, and, every 2 of light accepting part 244f advance exercise the illumination of the capable and n+1 of n in capable during the equal control of W2, make all to equate during the illumination of every row of the light accepting part 244f in 1 image duration.Particularly, lighting control section 42 is controlled as follows: using reading unit 244g for the border of reading the zero hour between the finish time between the capable reading duration of the n of light accepting part 244f and the capable reading duration of n+1 as benchmark P1, make n in capable from regulation time be carved into the illumination of throwing light on from benchmark P1 to the moment of regulation capable of W2 and n+1 during the illumination that benchmark P1 throws light on during W2 equate.Thus, by carrying out light source 41a luminous (continuous illumination) in the mode that during the capable illumination in capable with n+1 of n, W2 is connected continuously, the switching times that can make the luminous and shading in 2 row is 1 time.

And, as shown in Figure 3 (c), lighting control section 42 is controlled as follows to Lighting Division 41: at the adjacent n that crosses over light accepting part 244f capable and n+1 during capable, by reading unit 244g to adjacent n during the part between the capable and capable reading duration of reading of n+1 in ejaculation illumination light, and, every 2 of light accepting part 244f advance exercise the illumination of the capable and n+1 of n in capable during W3(W3<W2) equal control, make all to equate during the illumination of every row of the light accepting part 244f in 1 image duration.

Like this, in endoscopic system 1, even if there is the limit in the switching speed when luminous and extinguishing of toggle lights 41a, by controlling during 2 row are to illumination, also can shorten the time of exposure (with reference to Fig. 3 (c)) in 1 row, so, can expand the variable range (dimming scope of illumination) of time of exposure.

According to an embodiment of the invention described above, lighting control section 42 is controlled as follows to Lighting Division 41: in during the part between reading duration during 2 row of crossing over adjacent light accepting part 244f, that by reading unit 244g, adjacent each row is read, penetrate illumination light, and, every 2 of light accepting part 244f advance exercise the illumination in each row during equal control, make all to equate during the illumination of every row of the light accepting part 244f in 1 image duration.Thus, even if the switching speed while switching the lighting and extinguish of Lighting Division 41 exists the limit, also can prevent that exposure is uneven, and can expand the dimming scope of illumination.

And then, in an embodiment of the invention, owing to can controlling independently respectively the luminous quantity of the time of exposure of the electronic shutter based on imaging apparatus 244 and the illumination light based on light supply apparatus 4, so, can carry out the finer lightness control of texture.

In addition, in the present invention, can also apply the face light supply apparatus of formula in turn that irradiates successively the light with different wave length.

And, in the present invention, for example, for example, even the wave band light different from white illumination light, carry out green light (green light: 500nm～600nm) behind arrowband and the NBI(Narrow Band Imaging of these 2 kinds of wave bands of blue light (blue light: 400nm～500nm) by the logical filter of arrowband band: Narrow-Band Imaging) illumination light, also can using light source device 4.

And, in the present invention, also set handling device 3 and light supply apparatus 4 integratedly.

And, in the present invention, also can be provided as at leading section 24 LED of Lighting Division, imaging control part 244e or FPGA271 control this LED.

And in the present invention, control part 309 also can or be read timing according to the exposure of dim signal and imaging apparatus 244, and the flicker of Lighting Division 41 is carried out to PWM control.

And, in the present invention, can also be applied to 1 field interval that reading unit 244g reads from light accepting part 244f.

Label declaration

1: endoscopic system; 2: endoscope; 3: blood processor; 4: light supply apparatus; 5: display device; 41: Lighting Division; 41a: light source; 41b: light source drive; 42: lighting control section; 243: optical system; 244: imaging apparatus; 244a: sensor portion; 244b:AFE portion; 244c:P/S converter section; 244d: timing generator; 244e: imaging control part; 244f: light accepting part; 244g: reading unit; 301:S/P converter section; 302: image processing part; 303: lightness test section; 304: light modulation portion; 305: read address setting portion; 306: drive signal generating unit; 307: input part; 308: recording unit; 309: control part; 310: reference clock generating unit.

Claims

1. a camera system, is characterized in that, this camera system has:

Lighting Division, it penetrates the illumination light that subject is thrown light on;

Light accepting part, it is two-dimentional shape and is arranged with the pixel that generates the signal of telecommunication by receiving light and carrying out opto-electronic conversion;

Reading unit, it reads the described signal of telecommunication according to each horizontal line successively from described pixel; And

Lighting control section, it is controlled as follows to described Lighting Division: between the reading duration of the 1st horizontal line of crossing over described reading unit and in during between the reading duration of the 2nd horizontal line, penetrate the described illumination light of the pulse type centered by the finish time between the reading duration of described the 1st horizontal line, wherein, described the 2nd horizontal line is adjacent with described the 1st horizontal line and immediately after the 1st horizontal line, read.

2. camera system according to claim 1, is characterized in that,

Carry out the control of described lighting control section every 2 row.

3. camera system according to claim 1, is characterized in that,

Described camera system also has lightness test section, and this lightness test section detects the lightness of the light being received by described light accepting part,

Described lighting control section is according to the testing result of described lightness test section, and the PWM that carries out the pulse width that changes the described illumination light of described pulse type centered by the finish time between the reading duration of described the 1st horizontal line controls.